Such devices are already known, of the type comprising, on the one hand, means conveying the animals constituted by two endless belts facing each other and inclined so as to form a V-shaped passageway, and, on the other hand, two retractable electrodes mobile between a first active position for which they are placed on either side of the animal's head and a second retracted position allowing the stunned animal to be released.
In such devices, when it is desired to avoid manual application of the electrodes, which is expensive in manpower and not danger-free, the electrodes are mounted on a system driven by means of driving members between the two extreme positions, as in European Patent Application No. 019 332.
This latter arrangement leads to heavy, expensive and complex constructions. These systems do not ensure strict synchronism (which is necessary) between the advance of the animal (on the conveyor belts) and the electrode-holder carriage.
European Patent Application No. 067 482 provides the suspension of the electrodes from a pendulum-like system, which, however, follows a path which is curved and therefore not parallel to the linear path of the animal's head.